How to increment a sequential identifier in DynamoDB?

Question

I have an Invoice table in dynamodb with hash-sort combo key. The hash is a uuid "tenantId" and the sort is a uuid named "id" for the invoice. However I have a field called "InvoiceNumber" which is the human readable sequential identifier for the invoices.

What is the best/optimal way to increment the InvoiceNumber when I create a new record while ensuring uniqueness and avoid race conditions?

Edit: Uniqueness would need to be enforced for each hash or tenant but not across the table.

Is the InvoiceNumber unique within each tenantId or global? Also, does any of your items ever get deleted? — Andre.IDK
For now they can be deleted but if it helps the process I can archive them instead. As for uniqueness. It would need to be unique within the same hash (tenantId) but not across the entire table. — user3376065

jellycsc jellycsc · Accepted Answer · 2020-11-28T02:22:32

1

votes

Take a look at this Atomic Counter example. It is exactly what you are looking for.

How to increment a sequential identifier in DynamoDB?

1 Answers